Indoor Flying Models - Lighter Than Paper Airplanes Ray Harlan Semiretired MIT Aeronautical Engineer UPCOMING MEETINGS V OLUME 24 I SSUE 1 J ANUARY 2020 Cigar Box Bulletin RETIRED MEN’S ASSOCI ATION W ith two MIT Aero. degrees, Ray did MIT and Draper Lab. research for his professional career. But his real passion has always been building and compet- ing ultralight rubber-band-powered free-flight indoor models. He has won national competi- tions and established national records. His models typically weigh about a gram (the weight of a dollar bill) but can sometimes stay in the air for more that 3/4 hour. For his presentation to us, Ray entertained with the steady hand of an experienced showman. It was fun to watch. Paul Motyka made the intro- duction. On a long table, Ray displayed nearly a dozen examples which he had built. Most roughly resembled one or another common type of full- scale airplane (except for a bird-concept which flapped rear-mounted wings for thrust). Most had a large, 2-bladed nose propeller, with wings farther back that were bent up for the outer 1/4 of each wing. The bent-up wing ends tended to keep the model flying straight forward; any side -slip made the wing bank to create a temporary roll that returns the model to the original direc- tion. At the back end was a pair of horizontal tails with a vertical stabilizer (rudder) some- what farther forward. The latter was placed ahead of the tails to make it easier to twist slightly for creating deliberately-curved flight. The following picture shows these features. (See photo on page 6) Another model was a biplane concept with an electrically-powered pusher propeller behind the top wing. It roughly resembled the Wright Flyer which first flew in 1903 at Kitty Hawk, NC. All of the mostly-non-electric models were powered by a 16" long, natural-rubber-band loop, normally wound 2000+ turns to get the desired thrust and duration for competitions. (To store more energy into the rubber band for those times, Ray stretches and lubricates the Continued on Page 2 Continued on Page 3 Reporter: Bill Beebee Images from the Meeting 6 January Anniversaries 7 January Birthdays 8 Sorting Through Research on Aspirin 9 RMA Bulletin Board 10 The Calendar 11 INSIDE THIS ISSUE: January Meeting Minutes Ship’s Bell Rang at 10:00 AM Reporter: Dan Miller C hris Hammer called the meeting to or- der, asking for silencing of cell phones. Chris led members in the Pledge of Allegiance, followed by the singing of The Star Spangled Banner, accompanied by Ken Watson on the piano. New Members: Nick Veeder introduced 2 new members: Frank Wilson and Pat Mullin. Two additional new members were mentioned as well. Visitors: Nick said that there were no visitors. Paul Murphy introduced the traveler for the month: Jerry Brody attended the wedding of his granddaughter in Newark DE. Chris reminded us to give a quick, 1-minute
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Indoor Flying Models - Lighter Than Paper Airplanes
Ray Harlan
Semiretired MIT Aeronautical Engineer
UPCOMING
MEETINGS
V OLUME 24 ISSUE 1
JANUARY 2020 Cigar Box Bulletin
RETIRED MEN’S ASSOCIATION
W ith two MIT Aero. degrees, Ray did
MIT and Draper Lab. research for
his professional career. But his real
passion has always been building and compet-
ing ultralight rubber-band-powered free-flight
indoor models. He has won national competi-
tions and established national records. His
models typically weigh about a gram (the
weight of a dollar bill) but can sometimes stay
in the air for more that 3/4 hour. For his
presentation to us, Ray entertained with the
steady hand of an experienced showman. It
was fun to watch. Paul Motyka made the intro-
duction.
On a long table, Ray displayed nearly a dozen
examples which he had built. Most roughly
resembled one or another common type of full-
scale airplane (except for a bird-concept which
flapped rear-mounted wings for thrust). Most
had a large, 2-bladed nose propeller, with wings
farther back that were bent up for the outer 1/4
of each wing. The bent-up wing ends tended to
keep the model flying straight forward; any side
-slip made the wing bank to create a temporary
roll that returns the model to the original direc-
tion. At the back end was a pair of horizontal
tails with a vertical stabilizer (rudder) some-
what farther forward. The latter was placed
ahead of the tails to make it easier to twist
slightly for creating deliberately-curved flight.
The following picture shows these features.
(See photo on page 6)
Another model was a biplane concept with an
electrically-powered pusher propeller behind
the top wing. It roughly resembled the Wright
Flyer which first flew in 1903 at Kitty Hawk,
NC.
All of the mostly-non-electric models were
powered by a 16" long, natural-rubber-band
loop, normally wound 2000+ turns to get the
desired thrust and duration for competitions.
(To store more energy into the rubber band for
those times, Ray stretches and lubricates the
Continued on Page 2
Continued on Page 3
Reporter: Bill Beebee
Images from the Meeting 6
January Anniversaries 7
January Birthdays 8
Sorting Through Research on Aspirin 9
RMA Bulletin Board 10
The Calendar 11
INSIDE THIS ISSUE:
January Meeting Minutes Ship’s Bell Rang at 10:00 AM
Reporter: Dan Miller
C hris Hammer called the meeting to or-
der, asking for silencing of cell phones.
Chris led members in the Pledge of Allegiance,
followed by the singing of The Star Spangled
Banner, accompanied by Ken Watson on the piano.
New Members:
Nick Veeder introduced 2 new members: Frank
Wilson and Pat Mullin. Two additional new
members were mentioned as well.
Visitors: Nick said that there were no visitors.
Paul Murphy introduced the traveler for the month: Jerry Brody attended the wedding of his
granddaughter in Newark DE.
Chris reminded us to give a quick, 1-minute
C IGAR BOX BULLETIN P AGE 2
band.) Ray wound the loop on a portable jig which had a
torque meter on the other end from the winding crank. The
crank is attached to a gear box which multiplies the rubber
band twist by 20 for each turn of the crank. He used the
above-shown conventional design which he said had flown 47
min. But, for the coming flight demonstration, he put about
1000 turns into the band. He attached the front end of the
band to the propeller and the back end to a tie point 3/4 of the
way back on the fuselage.
Ray flew this conventional design (and, later, the bird-
concept) at about 2 feet/second speed, a few feet over the
heads of the RMA attendees in our meeting hall. The propel-
ler turned amazingly slowly - only about one revolution for
every two seconds - to generate the speed seen. (The flapping
wings of the later bird concept also "beat" more slowly than
would be expected.) Ray mentioned that "the room has ther-
mals" (RMA members' hot air) that effect the delicate flights.
Seeing the models fly, slowly and gracefully, over our heads,
the basic principle of long-duration flight became clear. With
the tiny energy of a twisted rubber band for propulsion, the
ultralights do not muscle their way through the air. They
"swim" through it with long, slow, graceful "strokes". The
propeller is very large and turns very slowly. With such slow
motion, the air flow over the propeller, wing, and tail surfaces
is very smooth. This is known as laminar flow. There is al-
most no turbulence, or eddies, in the air passage. This is ex-
tremely efficient flying because turbulence wastes energy.
With energy conserved at all times, long-time flights using
only a weak rubber band can actually be achieved.
Ray discussed the models as being constructed, in part, from
ple should continue taking it for cardiovascular benefits.
These news reports were the result of an updated 2019 prima-
ry prevention guidelines issued by the American College of
Cardiology (ACC) and the American Heart Association
(AHA). Unfortunately, some of the media coverage has po-
tentially created confusion for Americans who are taking aspi-
rin. First, as a cardiovascular physician I want to reinforce
that no one should stop or alter their aspirin regimen before
speaking with their doctor or health care provider. And sec-
ond, I will help sort through the news and the research on this
topic. There are two main categories of patients who take a
daily low-dose aspirin for cardiovascular (CV) event preven-
tion: patients who have not yet had serious cardiovascular
problems but may be at risk of having these problems AND
patients who have already experienced serious cardiovascular
problems like a heart attack or clot-related stroke. What the
updated guidelines tell us is that certain individuals in the first
category (have not yet had an event, often called primary pre-
vention) may not need to continue taking aspirin due to the
increased risks of bleeding outweighing the cardio-protection
benefit. Whether or not you are one of these individuals in
this category depends on your own personal risk factors,
which is why it is important to consult your doctor who can
help you understand the benefits and risks and what is best for
your health. For people in the secondary category – those who
have already experienced a cardiovascular event – aspirin can
be a lifesaver. Not only is it proven to help prevent another
heart attack or clot-related stroke, aspirin is also one of the
most extensively studied drugs in history. This is why aspirin
remains the cornerstone preventative therapy for secondary
prevention. In the United States, aspirin’s professional label is
approved for secondary prevention of a CV event. Some of
the media coverage around the new guidance was not clear on
this crucial distinction. For those who have already experi-
enced a heart attack, or clot-related stroke there is evidence
that discontinuing an aspirin regimen without a doctor’s guid-
ance can increase the risk of another heart attack by 63 per-
cent and a clot-related stroke due to a blood clot by 40 per-
cent. Cardiovascular disease is the number one cause of death
in the United States, affecting more than 92 million American
adults and causing about 2,200 deaths per day. That’s one life
every forty seconds. Each year 790,000 Americans alone will
suffer from a heart attack, while another 795,000 will have a
stroke. Many factors can contribute to a person’s risk of cardi-
ovascular disease, including high blood pressure, high choles-
terol and smoking – and almost half of Americans (47 per-
cent) have at least one of these risk factors. Clinical studies
and cardiovascular professional guidelines have continued to
support the lifesaving benefits of aspirin. Studies have found
that an aspirin regimen under the direction of a doctor can
help reduce the chances of a second heart attack by 31 percent
and a second clot-related stroke by 22 percent. Importantly,
even though aspirin is the gold standard of preventative thera-
py for those who have experienced a heart attack, clot-related
stroke, chronic stable and unstable angina, a stent placement
(PCI) or open heart surgery (CABG), it may not be for every-
one. Anyone who has questions about starting or continuing
an aspirin regimen should talk to their doctor. Aspirin is not
appropriate for everyone, so patients should talk to their doc-
tor before they begin an aspirin regimen. For more infor-
mation on safe and responsible use of OTC medicines, vis-
it www.KnowYourOTCs.org.
Disclosure: Dr. Gurbel is compensated by Bayer to advise on
cardiovascular health issues. Dr. Gurbel is the Director of
Cardiovascular Research at Sinai Hospital of Baltimore, MD and Director of the Sinai Center for Thrombosis Research
and Drug Development. He is also Professor of Medicine at
Johns Hopkins University School of Medicine and Adjunct
Professor of Medicine at Duke University School of Medicine.
Sorting Through Research on Aspirin...
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V OLUME 24 ISSUE 1 P AGE 10
RMA Bulletin Board
FOLKLORE FOR THE SEASON
• Fog in January brings a wet spring. • A favorable January brings us a good year. • If grass grows in January, it will grow badly the whole year. • A summerish January, a winter-
ish spring.
ANNUAL WEATHER SUMMARY NOVEMBER 2019 TO OCTOBER 2020 FROM THE OLD FARMER’S ALMANAC
Winter temperatures will be much above normal, on average, with the coldest periods in mid- and late January and early and late February. Precipitation will be above normal, with below-normal snowfall. The snowiest periods will occur in mid- and late January and early February. April and May will be warmer than normal, with precipitation near normal in the north and above normal in the south. Summer will be hotter and rainier than normal, with the hottest periods in mid-July and early to mid-August. September and October will be warmer and rainier than normal, with a tropical storm threat in early to mid-October.
C IGAR BOX BULLETIN P AGE 11
The Calendar
Do you know what day school starts in the fall or any other important date such as an anniversary?
Both you and the teachers need to show up on the same day and your spouse will be very upset if you for-
get your anniversary.
We find this easy because we have a good universal calendar. It became universal in 1949 when
Mao Tse-tung stated that China would use the Gregorian calendar. There are still special calendars in use
but the Gregorian is used by all six billion people on the earth.
In 48 BC, Julius Caesar sailed in a warship to Egypt in pursuit of Pompey his rival in a civil war. He
did many other things while he was there but one of them was to talk to the Egyptians about their calendar.
Their calendar was based on the sun and not the moon as were most calendars of the day.
The 52 year old Caesar returned to Rome as a dictator. He had with him his 21year old trophy
wife, Cleopatra queen of Egypt and Julius Jr. Things in Rome were a mess as the calendar was 90 days
behind the true year. Caesar fixed the year at 365 days. He named the months as we use them today and
decreed the months would be 30 and 31 days alternatively except for February. February would have 28
days. Every fourth year February would be 29 days and referred to as leap year.
What to do about the 90 extra days? Caesar extended the year 44 BC so it was 445 days long.
When the confusion was over all things were coordinated.
The church was mostly interested in when Easter should be. A decree from the Council of Bish-
ops stated in the 4th century that Easter would be the first Sunday after the first full moon after the
spring equinox. Why, because the only record available states that the first Easter occurred on a Sunday
with a full moon during Passover. It is still determined using the Jewish calendar which is lunar based.
Dennis the Little was a sixth century monk who was given the task of determining when future
Easters would be. The Roman calendar, in use at the time, started on the year Rome was founded. Dennis
the Little decided that Christ's birth was a better year. He also added BC and AD.
Julius Caesar's calendar began to slip as Rome's influence decreased. The church added holidays and
stopped using 30 days then 31 days for determining the length of a month. In 1582 Pope Gregory the XIII
ordered a revision of the calendar to the one we use today. So you have many people to thank for help deter-
mine when to return to school.
David R. Martinez is associate division head in the Cyber Security and Information Sciences Division at MIT
Lincoln Laboratory. In this capacity, he is focusing on the strategic and innovative directions of the division in
the areas of artificial intelligence, high performance computing, and cyber security. He is also a member of
MIT Lincoln Laboratory’s Steering Committee.
Mr. Martinez, who joined MIT Lincoln Laboratory in 1988, has served in various management positions. Dur-
ing 1993–1999, he held leadership roles in the Embedded Digital Systems Group. He served as associate head
(1999–2004) and head (2004–2010) of the Intelligence, Surveillance, and Reconnaissance (ISR) Systems and
Technology Division.
He has been the keynote speaker at both national and international conferences. He co-authored/co-edited the book titled High Per-
formance Embedded Computing Handbook: A Systems Perspective. In 2003, he was elected IEEE Fellow “for technical leadership
in the development of high performance embedded computing for real-time defense systems.” He holds three U.S. patents based on
his work in signal processing for seismic applications.
Mr. Martinez was awarded a bachelor’s degree from New Mexico State University, an MS degree from MIT, and the EE degree
jointly from MIT and the Woods Hole Oceanographic Institution in Electrical Engineering and Oceanographic Engineering. He com-
pleted an MBA from the Southern Methodist University.